Double-acting pump.



No. 806,388. PATENTED DEC. 5, 1905. v S. ZYLBERLAST.

DOUBLE ACTING PUMP.

APPLIOATION FILED APR. 22, 19os.

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No. 808,888. PATENTED DEC. 5, 1905.

s. ZYLBERLAST.

DOUBLE ACTING PUMP. APPLICATION FILED APR. 22, 1905.

4 SHEETS-SHBBT 3.

ww/aw *8 M" I aim M STANISLAS ZYLBE RLAST, F MANCHESTER, ENGLAND.

I l l I DouB E-Adi'iNG-PuMP. v v

- To all zuhmrz/it may concern:

Be it known that I, STANIsLAs ZYLBERLAST,

engineer, a subject of the Emperor of Russia,

and a resident of 409 Stretford road, Old Trafford, Manchester, in the county of Lancaster,

England, have invented a new and usefulImprovementin Double-Acting Pum'ps, of which the following is a specification.

This invention relates to double acting hitherto available for such purposes as aforesaid and may, as will be hereinafter explained, be constructed without suction-valves.

According to this invention a double-acting pump is provided with a hollow cy'linderor bucket made to work externally in aworking surface providedri'n the pump-.casingand internally upon afixed cylinder'supported in any suitable way, so that in the operation'of the pump the space left or formed outside the hollow cylinder or bucket and 'withinthe pump-casing and thespace left within'th'e 1101 low cylinder or bucket form two working 1 spaces, which enable each stroke of the hollow I cylinder or bucket'to expel fluid and. so make the manner which may be mostefl'ective for the pump double-acting, and can be utiliz d in the purpose for which the pump-may be intendedas, for example, by one space being used wholly or principally forflgaseous fluid,

while the other is used wholly or principally for liquid, or so that both spaces maybe used,

alike-as, for example, both for. gaseous fluid or both for liquidlorv both 'for' mixtures of gaseous fluid and liquid'andmay be con} structed tobe arranged vertic'ally or'in a hori- 'zontal or other desirable position.

According' to this (invention, in the form which will be described first by wayof ill'uQ.

.Jtration, a'hollow -cylinderwith. its top end" open is made to work tightly 'inan outer working surface within the pump-casing'as,

. for example, in aliner fixed thereim On the inside this cylinder passes and works over a shallowcylinder fixed in any suitable, manner within the pump-casing-as, forexample, by beingconnected by armsto any suitable part' a Specification of: Letters Patent. 3 Application filed Apiril22,i1905. seriaiu ztaevz.

away entirely with the highly- Patented Dec. 5, 1905.

r and receives thus another working surface,

which is made air-tight in any ordinary way.

.In the pump-casing are furnished partitions which, together with the body whereon the outer working surface is formed, divide the casing into two separate chambers and form workingcylinder or'bucket. The outer working surface is provided with a suitable number of portsas, for example, by being formed with rows of holes or by being formed in receptacles fordirecting the fluids to be pumped into. the inside and outside of the two or more parts, so that between each part and its neighbor a continuous circumferential opening is leftand these ports are provided in such positions that one allows the medium to p be pumped to flow below the working cylinder as soon as it passes such port on its. upward stroke, while another opens communication with the inside'of the working cylinder when.

a corresponding provision for the passage of flu1d..as, for example, a row of openings around the working cylindercomes in line with the said port on the downward stroke of the working cylinder or bucket. On its upward'stro'ke the cylinder or bucket may discharge fluid through valves fixed in a suitable positionfas, for example, 'in the hollow.cyl inder hereinbefore' mentio'nede-and on its downward stroke may discharge fluid through ,valvesfix'ed' in suitable positions as, for'example, atfthe bottom of the pump.

Pumps constructed according to this invention are especially-adapted for'work in con- 'junctionwith condensing'plants of any de-j scriptionsuch, for, example, as 'thoseusedfor creating vacuum in steam-engines, turbines, chemical apparatus, and in apparatus I of other ki-ndsand a pump. of this kind can: be used as aco'mbined dry-air pump and wa- .ter-pump in one unit, one part of'the bucket dealing with the air only and the other dealingwith the water, either circulating or condensed. Pumpsconstructed'according to this gines, as-in such a pump the pump-casing may be shaped in'such a way as to form a jet-con denser around. the pump and to have theoverflow-water-convey'ed direct into the top part of the same, so that the pump 'formsa completejcounter-current jet-condensing plant, in one single unit, thus making itpossibleto do parallel-current condensers.

uneconomical I00 l latter form are suited admirably for mill-env 23m IIO In the accompanying drawings, which are diagrammatic, and in all the figures of which the interior of the pump-casing c.

the same characters of reference are employed toindicate corresponding parts, Figure 1 is a vertical section taken on the plane indicated by the line A A of Fig. 2, illustrating a pump constructed according to the first hereinbe fore-described form of this invention; and Fig. 2 is a plan of the said pump with the upper cover of the pump-casing removed, these figures illustrating a pump intended specially 'for use in pumping either gas alone or gas with only a very small admixture of liquid. Fig. 3 is a vertical section taken on the plane indicated by the line B B of Fig. 4: of a pump used as a combined dry and wet pump, and Fig. 4 is a plan of such pump with the upper cover of the pump-casing removed, these figures illustrating one way of applying a pump constructed according to this invention in conjunction with a jet-condenser. Fig. 5, which is a vertical section of the pump taken on the plane indicated by the lineC O of Fig. 6, and Fig. 6, which is a plan of such pump with the upper cover of the pump-casing removed,show a modification of the pump shown in Figs. 1 and 2, which may be used as a dry pump only or a wet pump only. Fig. 7, which is a vertical section of a pump taken on the plane indicated by the line D D of Fig. 8, and Fig. 8, which is a plan of such pump with the upper cover of the pump-casing removed, represent the combination of a pump constructed according to this invention, generally in the manner illustrated in Figs. 3 and 4, with a countercurrent jet-condenser largely cast with a pump-casing in a single unit.

In Figs. 1 and 2 a; is the hollow cylinder with its top end open, and bis a liner in which the cylinder (4, which forms a piston or bucket, is made to work tightly in any suitable way. The liner 6 is shown as made to fit in the pump-casing 0, which is provided with a cover 0?, fitted tightly thereon, and is formed with three partitions e f g, which are shown as formed on the casing cand are furnished with central openings to receive and fit tightly around the liner 6. The liner Z) is secured to the upper partition 6. Internally the cylinder a is made to move upon a shallow cylinder h, fixed securely to the pump-casing 0, arms e', formed upon and extending from the cylinder 7L, being secured to projections 1', formed on The cylinder a is made air-tight around the shallow cylinder it by any suitable means. The lower partition 9 is shown as provided with downward extensions made to fit upon the inner edge of a flange 1:, formed around the upper part of the base Z of the pump. The partitions efg, acting in conjunction with the flange is, and the liner I),'divide the space within the casing c and below the cover (Z into four compartmentsnamely, two inlet-ehannelsm on", communicating with an opening a, by which the pump, and two receptacles 0 provided with outlet-openings (7 1', respectively, by

means of which the medium pumped may be discharged from thepump. At its lower part the base Z is provided with an opening and closed by a plate 8, secured to it and internally of a shape corresponding to that of the lower face of the cylinder or bucket a, which is shown as formed conical, so as better to deliver liquid in the manner now well known, and is connected to a piston rod 7,, passed through glands or stufiing-boxes a or, provided, respectively, on the cylinder it and cover (Z, and is guided in any suitable manner, so as to be incapable of allowing the cylinder at to be turned about its center line. Provision ismade in any suitable manner for the communication of the working space-namely, the space below the cylinder or bucket a and the space within such cylinder or bucket (t with the channels m m in the pump-casing 0. In the case illustrated the liner 5 is provided with openings w 10 arranged in two rows. By means of the lower rows of openings w the channel m is placed in communication with the interior of the liner 7), so that the medium to be pumped may pass below the cylinderor bucket a when such-cylinder or bucket (,6 is raised high enough to uncover the openings w, and by means of the upper row of openings w the channel m is placed in communication with the interior of the said cylinder or bucket (b above the bottom thereof, so that the medium to be pumped may enter the interior of the cylinder or bucket a when it is depressed low enough for openings it, provided in the cylinder or bucket a, to come into communication with the openings 41 The shallow cylinder h is shown as provided with valves ;1 made to open upward and arranged in conjunction with seatings and guards in any manner usual or suitable for air-pump valves, so that in the upward movement of the cylinder or bucket a the air or water in the interior of the cylinder or'bucket (b may be discharged past the valves 1 into the shallow cylinder It, whence it flows through the openings w or, eventually, over the top of the cylinder or bucket (L to the upper outlet 1' and so out of the pump. The base Z, to which the pump-casing c is connected by suitable means, is shown as provided with valves .2, made to open upward into the receptacle 1) and arranged in conjunction with seatings and guards in any manner usual .or suitable for air-pump valves, so that in the alone or gas with very little liquid at the up- 3 per outlet 1, and the liquid or theliquid with a proportion of gas at the lower outlet 9, the partition f serving to separate, more orless, the liquid from the gas at their entrance to the interior of the pump. The partition f becomes of special importance when a pump constructed according to this invention is used as a combined dry and wet pump, as it then separates entirely the air from the water, the

air being then discharged by theupstroke ofv the cylinder or bucket a and the water on the downstroke, or vice versa. Although in this way of using a pump it is preferable that the overflow-waterfrom the condenser shall be delivered into the lower chamber of the pump and that the air shall bedelivered into the higher-chamber, the water may be delivered into the higher chamber and the air into the lower.-

In the pump illustrated in Figs. 3 and 4, which is in general construction similar'to that illustrated in Figs. 1 and 2, the lower channel m is made to communicate with a pipe Z, by which the liquid to be pumped is led to the pump and through the one set of openings w, formed in the liner 5 into the working space below the cylinder or bucket 04 when such cylinder 01'' bucket is raised high enough, while the upper channel m is shown as made to communicate with an inlet 2 for the air to be pumped, and is also shown as made to communicate through the openings 20 formed in the liner 6 with the working space in the interiorof the cylinder or bucket a when depressed low enough for the openings :20 therein to come into communication c leave acircumfe'rential opening between them.

Figs. 7 and 8 represent the combination of a pump constructed according to this inven tion, generally in the manner illustrated in Figs. 3 and 4:, with a counter-current jetcondenser largely cast with the pump-casing c in asingle unit. In the pump illustrated by Figs. 7 and 8 the counter-current jet-condenser is constitutedby a cavity/1: in the pump-casing c, which is made to receive steam to be condensed and any air or other gas which may accompany it through an inlet 5, which cavity 4 is situate below a perforated partition 6, formed at the bottom of a channel 7 in the pump-casing c, which is in communi-v cation with a pipe 8, by means of which water or other liquid to be used as the condensing agent "is supplied to the said channel 7.

to extend around the casing c for a somewhat greater distance than the channel 7 and is shown as bounded atone end by a partition 9, i

which does not reach quite tov the cover d, so

that the air or other gas may pass from the cavity 9 over the partition and down a chan-- nel 10, formed. in the casing c, to the upper channel m The action of the pump illustrated in Figs. 7 and 8 being similar. to that of the pump illustrated by Figs. 3 and 4, it isobvious-that it will induce steam and air or other gas entering by the inlet 5 to tend to rise through the cavity 4 toward the upper end of the partition 9 in a direction more or less contrary to that in which water or other condensing liquid supplied through the channel 7 falls from the partition 6.

In the pump illustrated by Figs. 7 and 8, as in that illustrated by Figs. 3 and 4;, although it is preferable. that the overflow-water from of the pump, the water may be delivered into the higher chamber and the air or other gas intothe lower chamber.

The cylinder or bucket a of the pump illustrated by Figs. 3-and4 and the cylinder or bucket a of the pump illustrated by Figs. 7 and 8 are reduced in diameter for a little distance at the parts 11 at the lower circumfer ences, so that when at the highest part of their strokes the said cylinders or buckets shall allow the channel m m to be in communication, so that any inequality of pressure in the channels m m used with either of such cylinders or buckets a which might interfere with the proper flow of liquid into the pump may be equalized.

The pumps illustrated in Figs. 1 and 2,

Figs. 3 and 4. Figs. 5 and 6, and Figs. 7 and 8 are provided with hand-holes furnished with removable covers 12 where necessary, so that .access to the valves 1 2 and other parts of whereas in pumps constructed according to: I

thisinvention no part of the stroke of the plunger or bucket or piston is wasted.

Modern investigations into the action of &

condensing apparatus have proved amply that for equal duty a parallel-current condenser requires considerably larger displacement in the pump used with it than a counter-current condenser. Nevertheless, parallel current condensers are still in extensive use because of the compactness of the apparatus and because for a parallel-current condenser only one wet-air pump is required as against a separate dry-air pump and a separate w'aterpump, which are necessary for a counter-current condenser as hitherto constructed. By dividing a pump constructed according to this invention in the manner hereinbefore described, so that air shall be dealt with by the stroke of the piston or bucket in one direction, while the overflowwater is dealt with by the stroke of the piston or bucket in the other direction, the necessity for two different pumps is entirely obviated, and thus the use of parallel-current condensers is now no longer j ustified.

'Letters Patent, is

1. In a double-acting pump, the combination of an internal working surface upon a fixed part adapted to permit passage of fluid to be pumped, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and adapted to allow fluid to enter it and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

2. In a double-acting pump, the combination of an internal working surface upon a fixed part with openings to permit passage of fluid to be pumped, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and with openings to allow fluid to enter it and means to allow fluid pumped to issue from the interior of such cylinder, substantially as hereinbefore described.

3. In a double-acting pump, the combination of an internal working surface upon a fixed part with openings to permit passage of fluid to be pumped, an external working surface upon another fixed part, a hollow cylinworking surface and in the said internal working surface to work on and in such surfaces respectively and with openings to come opposite those of the internal working surface to allow fluid to enter it and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

4. In a double-acting pump, the combination of an internal working surface upon a fixed part adapted to permit passage of fluid to be pumped at more than one part of its internal surface, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and adapted to allow at part of its movementthe entrance of fluid from one part of the said internal workingsurface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described? 5. In a double-acting pump, the combination of an internal working surface u pon a fixed part adapted to permit passage of fluid to be pumped at two distinct parts of its internal surface, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such working surfaces respectively and adapted to allow at one part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

6. In a double-acting pump, the combination of an internal working surface upon a fixed part with openings to permit passage of fluid to be pumped at more than one part of its internal surface, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and with openings adapted to'allow at part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

7. In a double-acting pump, the combination of an internal working surface upon a IIO fixed part with openings to permit passage of fluid to be pumped at two distinct parts of its internal surface, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and with openings adapted to allow at der or bucket fitted upon the said external l part of its movement the entrance of fluid from one part of the saidinternal'working to be pumped at more than one part of itsinternalsurface means to separate into distinct currents the fl uid to be pumped on its way to the places of passage through the said internal working surface, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external Working surface and. in the said internal working surface-to work on and in such surfaces respectively and adapted to allow at part of its movement the entrance of fluid from one part of the said internal working surface and I means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

9. In a double-acting pump, the combination of an internal working surface upon a fixed part adapted to permit passage of fluid to be pumped at two distinct parts of its internal surface, a partition to separate into distinct currents the fluid to be pumped on its way to the places of passage through the said internal working surface, an external working surface upon another fixed part, a hollow cylinder, or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and adapted to allow at part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

10. In a double-acting pump the combination of an internal working surface upon a fixed part with openings to permit passage of fluid to be pumped at more than one part of its internal surface, means to separate into distinct currents the fluid to be pumped on the way to the said openings, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and with openings adapted to allow at part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbe fore described.

11. In a double-acting pump, the combination of an internal working surface upon a fixed part with openings to permit passage of fluid to be pumped at two distinct parts of its internal surface, a partition to separate into distinct currents the fluid to be pumped on the way to the said openings, an external working surface upon another fixed part, a hollow cylinder or bucket fittedupon the said external working surface and in the said internal working surface to work on andin such surfaces respectively and with openings adapted to allow at part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

12. In a double-acting pump, the combination of an internal working surface upon a fixedpart adapted to permit-passage of fluid to be pumped at more than one part of its internal surface, means to separate into distinct currents substantially of gas or liquid the fluid to be pumped on its way to the places of passage through the said internal Working surface, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and adapted to allow at part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore described.

13. In a double-acting pump, the combination of an internal working surface upon a fixed part adapted to permit passage of fluid to be pumped at two distinct parts of its internal surface, a partition to separate into distinct currents substantially of gas and liquid the fluid. to be pumped on its way to the places of passage through the said internal working surface, an external working surface upon another fixed part, a hollow cylinder or bucket fitted 'upon the said external working surface and in the said internal working surface to work on and in such surfaces respectively and' adapted to allow at part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket, substantially as hereinbefore 'described.

14. In a double-acting pump, the combination of an internal working surface upon a fixed part with openings to permit passage of fluid to be pumped at more than one part of its internal surface, means to separate into distinct currents of gas and liquid the fluid to be pumped on the way to the said openings, an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working'surface and in the said internal working surface to work on and in such surfaces respectively and with openingsadapte'd to allow at part of its movement the entrance of fluid from one vpart of I an external working surface upon another fixed part, a hollow cylinder or bucket fitted upon the said external working surface and in the said internal working surface towork on and in suchsurfaces respectively and with openings adapted to allow at part of its movement the entrance of fluid from one part of the said internal working surface and means to allow fluid pumped to issue from the interior of such cylinder or bucket substantially as hereinbefore described.

16. In a double-acting pump, the combination with a pump-casing furnished within with an internal working surface adapted to permit passage of fluid to be pumped, a fixed cylinder within the said pump-casing and furnished with an external working surface, a hollow cylinder or bucket adapted to allow fluid being pumped to enter it, fitted and made to work externally against theinternal working surface within the pump-casing and internally against the external working surface of the said fixed cylinder, substantially as hereinbefore described.

17. In a double-acting pump, the combina tion of a pump-casing furnished within with an internal Working surface with openings to permit passage of fluid to be pumped, a fixed cylinder within the said pump-casing and furnished with an external working surface and a hollow cylinder adapted to allow fluid being pumped to enter-it and a hollow cylinder or bucket fitted and made to work externally against the internal working surface within the pump-casing and internally against the external working surface of the said fixed cylind er, substantially as hereinbefore described.

18. In a double-acting pump, the combination of a pump-casing furnished within with an internal working surface adapted to permit passage of fluid to be pumped, a fixed cylinder within the said pump-casing and furnished with an external working surface and a hollow cylinder or bucket with openings to allow the fluid being pumped to enter it, fitted and made to work externally against the internal working surface within the pump-casing and internally against the external surface of the said fixed cylinder, substantially as hereinbefore described.

19. In a double-acting pump, the combination of a pump-casing furnished within with an internal working surface adapted to permit passage of fluid to be pumped, a fixed cylinder within the said pump-casing and furnished with an external working surface and a hollow cylinder or bucket with an inlet to allow fluid to enter it fitted and made to work externally against the internal working surface within the pump-easing and internally against the external surface of the said fixed cylinder, substantially as hereinbefore described.

20. In a double-acting pump, the combination of a pump-casing adapted to admit the fluid to be pumped,means to divideinto distinct currents, substantially gaseous and liquid respectively, the fluid to be pumped as it enters the said casing an internal working surface within the said casing adapted to permit the passage of fluid to be pumped at distinct parts, a fixed cylinder within the said pump-casing and furnished with an external working surface and a hollow cylinder or bucket adapted to allow the fluid being pumped to enter it and fitted and made to work externally against the internal working surface within the pumpcasing and internally against the external working surface of the said fixed cylinder, substantially as hereinbefore described.

21. In a double-acting pump, the combination of a pump-casing adapted to admit the fluid to be pumped, a partition to divide into distinct currents, substantially gaseous and liquid respectively, the fluid to be pumped as it enters the said casing, an internal working surface within the said casing adapted to permit the passage of fluid to be pumped at distinct parts, a fixed cylinder within the said pumpcasing and furnished with an external working surface and hollow cylinder or bucket adapted to allow the fluid being pumped to enter it at part of its movementfrom one part of the said internal working surface and fitted and made to work externally against the internal working surface within the pump-casing and internally against the external working surface of the said fixed cylinder substantially as hereinbefore described.

22. In a double-acting pump the combination of a pump-casing adapted to admit the fluid to be pumped means to divide into distinct currents, substantially gaseous and liquid respectively, the fluid to be pumped as it enters the said casing, an internal working surface within the said casing adapted to permit the passage of fluid to be pumped at distinct parts, a fixed cylinder within the said pump-casing and furnished with an external working surface and a hollow cylinder or bucket with openings to allow the fluid being pumped to enter it at part of its movement from one part of the said internal working surface and fitted and made to work externally against the internal working surface within the pump-casing and internally against the external surface of the said fixed cylinder, substantially as hereinbefore described.

28. In a double-acting pump, the combination of a pump-casing adapted to admit the fluid. to'be pumped a partition to divide into distinct currents, the substantially gaseous and liquid respectively, the fluid to be pumped as it enters the said casing, an internal working surface within the said casing adapted to permit the passage of fluid to be pumped at distinct parts, a fixed cylinder within the said pump-casing and furnished with an external working surface and a hollow cylinder or bucket with openings to allow the fluid being pumped to enter it at part of its movement, from one part of the said internal working surface and fitted and made to work externally against the internal working surface within the pump-casing and internally against the external surface of the said fixed'oylinder, substantially as hereinbefore described. I

24. In a double-acting pump, the combinadistinct currents, substantially gaseous liquid respectively, at different parts, one in communication with the said channel for gaseous fluid and the other in communication with the condensing-chamber aforesaid, a fixed cylin-' der within the said pump-casing adapted to permit the passage of substantially gaseous fluid and liquid at distinct parts, a fixed cylinder within the said pump-casing and furnished with an external working surface anda hollow cylinder or bucket adapted to allow the substantially gaseous fluid to be pumped to enter it at part of its movement, from one part of the said internal working surface and fitted and made to work externally against the internal working surface within the pumpcasing and internally against the external Working surface of the said fixed cylinder,

substantially as hereinbefore described.

25. In a double-acting pump, the combination of a pump-casing divided by a perforated partition into chambers one serving as a supply-channel for the condensing liquid and the other'as a condensing-chamber and with a channel for gaseous fluid in communication with such condensing-chamber, an internal working surface withinthe said casing adapted to permit the fluid to be pumped in distinct currents, substantially gaseous and liquid respectively, at diflerent parts, one in communication with the said channel for gaseous fluid and the other in communication with the condensing-chamber aforesaid, a fixed cylinder within the said pump-casing with openings to permit the passage of substantially gaseous fluid and liquid at distinct parts, and a fixed cylinder within the said pump-casing and furnished'with an external working surface,and a hollow cylinder or bucket with openings to allow the substantially gaseous fluid to be pumped to enter it at part of its movement from one part of thesaid internal working surface and fitted and made to work externally against. the internal working surface. within the pump-casing and internally against the external working surface of the said fixed cylinder, substantially as hereinbefore described.

In testimony that I claim the foregoing as my invention I have signed my name, in presence of two witnesses, this 10th day of April,

STANISLAS ZYLBERLAST. Witnesses: HOWARD OHEETHAM, RUTH MAGDALENE WILSON. 

